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Concept: Human skeleton

172

A finding of high BMD on routine DXA scanning is not infrequent and most commonly reflects degenerative disease. However, BMD increases may also arise secondary to a range of underlying disorders affecting the skeleton. Although low BMD increases fracture risk, the converse may not hold for high BMD, since elevated BMD may occur in conditions where fracture risk is increased, unaffected or reduced. Here we outline a classification for the causes of raised BMD, based on identification of focal or generalized BMD changes, and discuss an approach to guide appropriate investigation by clinicians after careful interpretation of DXA scan findings within the context of the clinical history. We will also review the mild skeletal dysplasia associated with the currently unexplained high bone mass phenotype and discuss recent advances in osteoporosis therapies arising from improved understanding of rare inherited high BMD disorders.

Concepts: Osteoporosis, Bone, Bone density, Density, Skeletal system, Dual energy X-ray absorptiometry, Human skeleton, Skeleton

90

Preceramic human skeletal remains preserved in submerged caves near Tulum in the Mexican state of Quintana Roo, Mexico, reveal conflicting results regarding 14C dating. Here we use U-series techniques for dating a stalagmite overgrowing the pelvis of a human skeleton discovered in the submerged Chan Hol cave. The oldest closed system U/Th age comes from around 21 mm above the pelvis defining the terminus ante quem for the pelvis to 11311±370 y BP. However, the skeleton might be considerable older, probably as old as 13 ky BP as indicated by the speleothem stable isotope data. The Chan Hol individual confirms a late Pleistocene settling of Mesoamerica and represents one of the oldest human osteological remains in America.

Concepts: United States, Mexico, Cave, Human skeleton, Skeleton, Mexico City, Speleothem, Quintana Roo

71

The assignment of biological sex to archaeological human skeletons is a fundamental requirement for the reconstruction of the human past. It is conventionally and routinely performed on adults using metric analysis and morphological traits arising from postpubertal sexual dimorphism. A maximum accuracy of ∼95% is possible if both the cranium and os coxae are present and intact, but this is seldom achievable for all skeletons. Furthermore, for infants and juveniles, there are no reliable morphological methods for sex determination without resorting to DNA analysis, which requires good DNA survival and is time-consuming. Consequently, sex determination of juvenile remains is rarely undertaken, and a dependable and expedient method that can correctly assign biological sex to human remains of any age is highly desirable. Here we present a method for sex determination of human remains by means of a minimally destructive surface acid etching of tooth enamel and subsequent identification of sex chromosome-linked isoforms of amelogenin, an enamel-forming protein, by nanoflow liquid chromatography mass spectrometry. Tooth enamel is the hardest tissue in the human body and survives burial exceptionally well, even when the rest of the skeleton or DNA in the organic fraction has decayed. Our method can reliably determine the biological sex of humans of any age using a body tissue that is difficult to cross-contaminate and is most likely to survive. The application of this method will make sex determination of adults and, for the first time, juveniles a reliable and routine activity in future bioarcheological and medico-legal science contexts.

Concepts: Protein, Male, Evolution, Molecular biology, Biology, Sexual dimorphism, Sex, Human skeleton

52

King Philip II was the father of Alexander the Great. He suffered a notorious penetrating wound by a lance through his leg that was nearly fatal and left him lame in 339 B.C.E. (i.e., 3 y before his assassination in 336 B.C.E.). In 1977 and 1978 two male skeletons were excavated in the Royal Tombs II and I of Vergina, Greece, respectively. Tomb I also contained another adult (likely a female) and a newborn skeleton. The current view is that Philip II was buried in Tomb II. However, the male skeleton of Tomb II bears no lesions to his legs that would indicate lameness. We investigated the skeletal material of Tomb I with modern forensic techniques. The male individual in Tomb I displays a conspicuous case of knee ankylosis that is conclusive evidence of lameness. Right through the overgrowth of the knee, there is a hole. There are no obvious signs that are characteristic of infection and osteomyelitis. This evidence indicates that the injury was likely caused by a severe penetrating wound to the knee, which resulted in an active inflammatory process that stopped years before death. Standard anthropological age-estimation techniques based on dry bone, epiphyseal lines, and tooth analysis gave very wide age ranges for the male, centered around 45 y. The female would be around 18-y-old and the infant would be a newborn. It is concluded that King Philip II, his wife Cleopatra, and their newborn child are the occupants of Tomb I.

Concepts: Human skeleton, Skeleton, Alexander the Great, Philip II of Spain, Philip II of Macedon, Olympias, Philip III of Macedon, Alexander IV of Macedon

38

Seventy-one individuals from the late Neolithic population of the 7000-year-old site of Hódmezővásárhely-Gorzsa were examined for their skeletal palaeopathology. This revealed numerous cases of infections and non-specific stress indicators in juveniles and adults, metabolic diseases in juveniles, and evidence of trauma and mechanical changes in adults. Several cases showed potential signs of tuberculosis, particularly the remains of the individual HGO-53. This is an important finding that has significant implications for our understanding of this community. The aim of the present study was to seek biomolecular evidence to confirm this diagnosis. HGO-53 was a young male with a striking case of hypertrophic pulmonary osteopathy (HPO), revealing rib changes and cavitations in the vertebral bodies. The initial macroscopic diagnosis of HPO secondary to tuberculosis was confirmed by analysis of Mycobacterium tuberculosis complex specific cell wall lipid biomarkers and corroborated by ancient DNA (aDNA) analysis. This case is the earliest known classical case of HPO on an adult human skeleton and is one of the oldest palaeopathological and palaeomicrobiological tuberculosis cases to date.

Concepts: Cell, Metabolism, Skeletal system, Tuberculosis, Mycobacterium, Neolithic, Human skeleton, Skeleton

35

In November and December 2013, unidentified human skeletal remains buried in a mokgwakmyo (a traditional wooden coffin) were unearthed while conducting an archaeological investigation near Gyeongju, which was the capital of the Silla Kingdom (57 BCE- 660 CE) of ancient Korea. The human skeletal remains were preserved in relatively intact condition. In an attempt to obtain biological information on the skeleton, physical anthropological, mitochondrial DNA, stable isotope and craniofacial analyses were carried out. The results indicated that the individual was a female from the Silla period, of 155 ± 5 cm height, who died in her late thirties. The maternal lineage belonged to the haplogroup F1b1a, typical for East Asia, and the diet had been more C3- (wheat, rice and potatoes) than C4-based (maize, millet and other tropical grains). Finally, the face of the individual was reconstructed utilizing the skull (restored from osseous fragments) and three-dimensional computerized modeling system. This study, applying multi-dimensional approaches within an overall bio-anthropological analysis, was the first attempt to collect holistic biological information on human skeletal remains dating to the Silla Kingdom period of ancient Korea.

Concepts: Seoul, Human skeleton, Skeleton, Goguryeo, History of Korea, Balhae, Three Kingdoms of Korea, Silla

28

Richard III was the last king of England to die in battle, but how he died is unknown. On Sept 4, 2012, a skeleton was excavated in Leicester that was identified as Richard. We investigated the trauma to the skeleton with modern forensic techniques, such as conventional CT and micro-CT scanning, to characterise the injuries and establish the probable cause of death.

Concepts: Human skeleton, Skeleton, Henry VII of England, Edward V of England, Richard III of England, Edward IV of England, Leicester, Battle of Bosworth Field

28

In recent years there has been growing interest in the spatial properties of osteocytes (including density and morphology) and how these potentially relate to adaptation, disease and aging. This interest has, in part, arisen from the availability of increasingly high-resolution 3D imaging modalities such as synchrotron radiation (SR) micro-CT. As resolution increases, field of view generally decreases. Thus, while increasingly detailed spatial information is obtained, it is unclear how representative this information is of the skeleton or even the isolated bone. The purpose of this research was to describe the variation in osteocyte lacunar density, morphology and orientation within the femur from a healthy young male human. Multiple anterior, posterior, medial and lateral blocks (2mm×2mm) were prepared from the proximal femoral shaft and SR micro-CT imaged at the Advanced Photon Source. Average lacunar densities (±standard deviation) from the anterior, posterior, medial and lateral regions were 27,169±1935, 26,3643±1262, 37,521±6416 and 33,972±2513 lacunae per mm(3) of bone tissue, respectively. These values were significantly different between the medial and both the anterior and posterior regions (p<0.05). The density of the combined anterior and posterior regions was also significantly lower (p=0.001) than the density of the combined medial and lateral regions. Although no difference was found in predominant orientation, shape differences were found; with the combined anterior and posterior regions having more elongated (p=0.004) and flattened (p=0.045) lacunae, than those of the medial and lateral regions. This study reveals variation in osteocyte lacunar density and morphology within the cross-section of a single bone and that this variation can be considerable (up to 30% difference in density between regions). The underlying functional significance of the observed variation in lacunar density likely relates to localized variations in loading conditions as the pattern corresponds well with mechanical axes. Lower density and more elongate shapes being associated with the antero-posterior oriented neutral axis. Our findings demonstrate that the functional and pathological interpretations that are increasingly being drawn from high resolution imaging of osteocyte lacunae need to be better situated within the broader context of normal variation, including that which occurs even within a single skeletal element.

Concepts: Bone, Density, Skeletal system, Human skeleton, Skeleton, Synchrotron, Osteocyte, Advanced Photon Source

27

Until final completion of maturation processes at the age of approximately 18 years, determination of the skeletal age of the hand plays a central role in forensic age diagnostics in living persons in criminal proceedings. In this process, assessment of hand radiographs relies primarily on the stage of development of the epiphyseal nuclei, the increase in size of the individual bones and of the hand skeleton as a whole, changes in the shape of the various skeletal elements and ossification of the epiphyseal plates. To achieve this, there are a variety of methodological approaches based on two different fundamental principles. The methods proposed by Greulich and Pyle, Thiemann et al. and Gilsanz and Ratib rank among the so-called atlas techniques, whilst the methods proposed by Tanner et al. and Roche et al. are classified as so-called bone-specific techniques. In order to be applicable in the field of criminal procedure, the methods of estimating the skeletal age of the hand developed with clinical aspects in mind must satisfy the demands of a high degree of estimate accuracy and good reproducibility of the estimated results. In the course of the present study, a study population of 92 persons was used to compare the above-mentioned atlas and bone-specific techniques for determining hand skeleton age in view of these qualitative criteria. Estimate accuracy was studied using Pearson’s correlation coefficients, and weighted kappa coefficients were determined for studying the intra-and interobserver agreement of an estimate result. In the inter-method comparison, a basically good agreement was shown between the skeletal ages and the chronological age of the test persons on the one hand and the skeletal age diagnoses of one or of two examiners on the other. No general advantage of the methodological approach of the bone-specific technique was discernible in the course of comparison; in the female gender, particularly, the RUS2 and RUS3 score of the method of Tanner et al. proved unfavourable. For age estimation practice in criminal proceedings, the atlas methods of Greulich and Pyle and Thiemann et al. are particularly recommendable.

Concepts: Bone, Statistics, Pearson product-moment correlation coefficient, Approximation, Estimation, Endochondral ossification, Human skeleton, Legal burden of proof

27

Osteopetrosis is a rare congenital (autosomal type) disorder of the skeletal system. Several variants have been described in the literature with grossly variant prognosis and clinical behaviour. Several reports of intractable osteomyelitis of the jaw bones secondary to osteopetrosis, particularly the mandible, have been published widely. However, there is no published report of the complete mandible sequestrating de novo, in the literature. An overview of this spectrum of sclerotic bone disease, its presentation in the oro-facial region, the diagnostic challenge it poses and the management dilemma it offers to the maxillofacial surgeon is discussed and a protocol for managing this disease effectively is presented. A clinical illustration of the complexities of management of osteopetrosis-induced osteomyelitis of jaw bones is demonstrated with a very rare case in which the entire mandible had sequestrated.

Concepts: Bone, Skeletal system, Surgery, Intramembranous ossification, American College of Surgeons, Human skeleton, Skeleton, Jaw